Q: I frequently get an “out of memory” message on my Windows 7 PC, and usually have to shut down the PC to get rid of it. What can I do about this?

Margaret Lonergan, Minneapolis

A: There are several possible reasons you got the “out of memory” message, but often it means your PC’s RAM (random access memory) is full.

RAM, or computer chip memory, holds the data you are working with at the moment, so it’s typically the first storage area that fills up. There are two possible solutions: Close some programs or browser windows to free up memory space for others. Alternatively, you can run an automated software fix from Microsoft (see tinyurl.com/y948cbn4) that rearranges the way your PC uses memory, devoting more of it to running programs.

But those actions may not be enough to solve the problem if your PC has too little RAM. To find out whether your PC has enough RAM, go to Control Panel and click on “system.” In the resulting menu, look at “installed memory (RAM)” (the number of gigabytes) and “system type” (either a 32-bit or 64-bit version of Windows 7.)

If your PC has a 32-bit version of Windows 7, it should have 4 gigabytes of RAM. If it’s the 64-bit version, it should have at least 8 gigabytes of RAM. If your PC has less RAM than I have suggested, ask a repair shop to install more.

If that doesn’t solve the problem, you may be getting the “out of memory” message because your PC’s hard disk is too full. (If your RAM memory is full, the computer will try to borrow some empty storage space on the hard disk to handle the RAM overflow. If there is too little hard disk space available, the borrowing process won’t work.)

You can find out how full the hard disk is by going to Windows Explorer and right-clicking the “C” disk (which is the hard disk.) In the resulting menu, click “properties.” In the next list, check the “used space” and “free space” headings to see how much of the disk is currently in use.

If the hard disk has less than a few hundred megabytes of free space, you will need to delete some data. First empty your PC’s recycle bin, then empty the cache, or temporary storage, used by your Web browser (see tinyurl.com/brfbqmx). If that’s not enough, you will have to delete some programs or personal data (save your personal data to a flash drive first.)

Q: My friends with the CenturyLink e-mail addresses q.com and centurylink.net receive only about one-third of the e-mails I send them from my comcast.net address. I’m notified that the others can’t be delivered. But I receive all the messages my friends send me. Why does this happen, and what can I do about it?

Pat Dahlman, White Bear Lake

A: You are most likely caught up in a blame game between internet service providers.

If customers on provider A’s network send too much spam (junk e-mail) to customers on provider B’s network, B temporarily blocks all e-mail coming from A. In essence, B is warning A to do a better job of policing its own network to eliminate spammers.

As an experiment, try a free e-mail account from Google, Yahoo or Microsoft to see if more of your e-mails are received.

E-mail tech questions to steve.j.alexander@gmail.com. Include name, city and telephone number.

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